JPS6322695A - Ink cartridge for fountain pen, etc. - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an ink cartridge such as a fountain pen according to the generic concept of claim 1.

Such cartridges are formed as elongated hollow synthetic resin rotating bodies filled with ink or other writing liquid, closed at one end and having an outlet at the other end. In the case of disposable cartridges, this outlet is formed as a breakable soft part, spherical valve, etc., but in the case of ink pen cartridges, for example, it is formed as the open end of a cylindrical ink cartridge that can be attached to the writing head of an ink pen. can also be formed. However, the invention also relates in a very general sense to an ink reservoir fixedly integrated into a fountain pen without a cartridge. This is because the principles of the present invention can be applied to this as well.

During writing with a fountain pen, the ink present in the ink cartridge is used, but this ink cannot be compressed into the cartridge itself and must be replaced by air; generally this means that the cartridge must be straight before exiting. For example, if a person is carrying a fountain pen hanging from the opening of a jacket pocket, the fountain pen may be placed anywhere on the fountain pen, preferably from the writing tip toward the outlet, and the air can flow into the cartridge. This is done by means of an air groove such as that introduced into the

When a fountain pen warms up or the air around it drops in pressure, for example if you take it on an airplane, overpressure builds up inside the cartridge and air escapes.

If you hold the fountain pen straight and the outlet of the ink cartridge is facing upward, the pressure can be easily balanced.

However, if the outlet opening is clogged with ink, the ink will necessarily be forced out through the vent groove, otherwise the check valve will not be able to withstand the resulting internal problems.

The production of ventilation grooves in fountain pens is expensive and makes the manufacture of particularly simple writing instruments extremely difficult. Furthermore, the effectiveness of such ventilation channels is hindered by the fact that they are blocked by overflowing and dried ink, so that sufficient ventilation is no longer possible. Intermittent replenishment of writing fluid occurs,
Accordingly, the function of the writing instrument becomes unreliable.

It was in principle possible to provide the ink cartridge with one or more check valves that would allow air to enter but prevent writing fluid from leaving. However, in order to be able to reliably prevent such discharge of writing fluid, a closing force for the valve body is required, which must first be overcome by the invading air. On the other hand, however, the ink discharge must be as uniform as possible.

Such a process is not possible as it would lead to a highly uneven and interrupted ink supply.

Starting from this state of the art, the present invention provides the above-mentioned solution for the purpose of replenishing the dry writing fluid without attaching additional devices to the writing instrument and without the risk of clogging the dry writing fluid. It is based on the problem of producing such an ink cartridge.

The above problem is a fountain pen with an elongated case with an outlet at one end, characterized in that the case wall has additional ventilation holes, which are closed with a breathable but ink-impermeable sealing substance. Solved by Ink Patrone such as.

According to the invention, the ink cartridge is provided with a further opening covered by a sealing material for ink drainage. This material allows the passage of air, more preferably penetration, from the outside to the inside of the ink cartridge, but it certainly prevents the passage of writing fluid from the inside to the outside, perhaps especially by means of the pore openings. Here, an overpressure is maintained inside the ink cartridge in order to prevent in any case ink or writing fluid from penetrating into the sealing material and blocking the stoma or comparable opening. It is preferable to select as follows.

Additional vents covered with a sealing substance can in principle span part or all of the peripheral wall of the ink cartridge. In the latter case, the entire ink cartridge is actually formed from a possibly further hardened sealing material. A particular advantage of such a configuration is that even in the case of a completely filled ink cartridge containing only one small air bubble, this air bubble is attached to an additional vent, so that the Air can easily escape to the outside when the pressure inside the ink cartridge increases. However, according to a preferred embodiment of the invention, an additional vent is arranged at the end of the ink cartridge remote from the outlet. This is because such an arrangement allows for a simple and reliable application of the sealing material, which is able to withstand the overpressure generated inside the ink cartridge.

In principle any microporous material or fleece can be used as the blocking material, but in the latter case care should be taken that the material itself does not become wetted by the writing fluid. However, according to a further preferred embodiment of the invention, the sealing material is produced by a biaxially oriented PTFE membrane as described in DE 21 23 318. In the case of this septum/membrane, fibers 11 (fibrils) are created in which nodules of material are connected to each other by a special drawing process.
occurs. There are small interstices between the fibers (hereinafter referred to as "for simplicity") that exhibit a morphology different from the pores of any other microporous material
small pores) are generated. By controlling the manufacturing parameters, fiber length and distance can be adjusted. A particular advantage in this case lies in the strong stirrability and anti-adhesive properties of PTFH: thus not only is the side of the sealing substance facing the writing fluid prevented from sticking, but also overpressure of writing fluid is removed from the diaphragm. When adjacent to such PTFE
- The rebound effect of the diaphragm on the writing fluid becomes very large, but the passage of air in one or both directions is not obstructed. For example, when a fountain pen equipped with an ink cartridge according to the present invention is accidentally carried with the tip of the ink cartridge, that is, the outlet of the ink cartridge downward, on an airplane during ascending flight,
The air bubble inside the ink cartridge adjoins the PTFE diaphragm, so that a pressure equilibrium across the diaphragm can occur; the fountain pen itself will not be ejected in this undesired position.

The length of the fiber can be translated into "pore size," which, although related to permeability, is not related to the feedstock dimensions of the free volume. 0.02 to 5μ, preferably 0
．． A pore size of 0.02 to 0.2 μm is advantageous.

However, since the PTFE-diaphragm does not optimize its mechanical strength considering its permeability, it is better to have a large number of small holes in the walls or bottom of the ink cartridge, so that only relatively small openings in the membrane can intertwine freely. can be provided and covered with the diaphragm from the inside or outside. However, according to a preferred embodiment of the invention, a carrier layer is provided which is formed into a laminate together with the PTFE diaphragm before being attached to the ink cartridge. The carrier layer can here be provided on one or both sides of the diaphragm. In the latter case the diaphragm is better protected.

Preferred materials for the carrier layer are woven fabrics of polyethylene or polypropylene, nonwoven fabrics of polypropylene or polyester and polyurethane foams.
PUC is also suitable. Non-woven fabrics include integrally molded grids or fleeces.

When using foam or fleece, however, a layer on the diaphragm surface remote from the interior of the ink cartridge should be placed on the diaphragm surface remote from the interior of the ink cartridge, in order to prevent the carrier layer from absorbing the writing fluid so well that the resistance to the passage of air becomes significantly high. Care must be taken in applying this carrier.

This preferred implementation B8! In this case, an integrated grid made of polypropylene, ie a perforated tube, is laminated on one or both sides with a PTFE diaphragm, preferably with a pore size of 0.2 to 0.02 .mu.m. The thickness of the diaphragm and the perforated cylinder is about 0.8 mm, and after the lamination process is finished, a laminate with a total thickness of about 0.35 mm is obtained. This laminate exhibits very high strength and has the advantage that the perforated polypropylene layer can be easily welded to the thermoplastic synthetic resin from which the ink cartridge is formed.

The subject matter of the invention will now be explained in more detail by means of an exemplary embodiment with reference to the accompanying drawings: The illustrated ink cartridge has an integral peripheral wall 1, which wall is formed from a rotationally symmetrical tube of substantially conical shape. The floor or wide end is open.

An outlet 2 is arranged in the narrow necked end.

The floor covers the free end of the peripheral wall and is formed from a laminate 3 lying in a radial plane relative to it.

The 8μ layer 3 is formed from a perforated PP tube 4 and an expanded PTFE membrane 5, which membrane is fixed to the perforated tube 4.

The perforated cylinder 4 is welded at the end of the peripheral wall l, so that the stack 3 is connected to the peripheral wall 1 in a fluid-tight manner.

The illustrated ink cartridge is filled with ink.

When arranging two ink cartridges in sequence and storing them in one fountain pen as shown in the figure, the PTFE-diaphragm 5
Another 8 layers of perforated tubes are placed on the outside of the cartridge, so that the neck of the peripheral wall 1 of the rear cartridge or the outlet 2 of the cartridge is located in front of the cartridge 8.
It is advantageous to reinforce the laminate 3 so that it cannot be punctured when resting on it.

The invention relates not only to the illustrated ink cartridge, but also to a writing instrument equipped with such a cartridge or with a similar storage chamber for writing fluid.

Next, a second invention closely related to the above-mentioned invention will be explained.

The present invention includes an ink reservoir case containing ink,
The present invention relates to an ink cartridge whose case is provided with an ink outlet and a ventilation device.

As is well known, in such an ink cartridge, the ink outlet is formed as a weak point, a globe valve, etc. that can be easily penetrated. In the case of a drafting ink pen, the ink outlet end is completely open. In the case of ink cartridges for ink jet writing, such as those used, for example, in printing presses, the ink outlet end is connected to an ink tube leading to a jet head from which ink is ejected in droplets.

In the case of the above-mentioned ink cartridges, especially in the case of fountain pen ink cartridges, and also in the case of fountain pens with a fixedly mounted ink reservoir, the cartridge gradually empties during writing. Since the walls of the cartridge are generally rigid, if you want to avoid the vacuum created by the flow of a certain amount of ink from interfering with the continuous flow of ink from the ink outlet end, venting is necessary. equipment must be provided. However, providing a simple ventilation groove in the ink cartridge is problematic because under certain conditions it can result in undesirable ink flow.

As mentioned above, Applicant discloses a venting device in the form of a breathable but liquid impermeable diaphragm forming the end of the cartridge opposite the ink outlet.

However, although on the whole these measures achieve the desired ventilation, under certain conditions - for example when the temperature rises or when the ink cartridge is in a constant state - the ink can flow out rapidly through the ink outlet. It has also been observed that the fountain pen becomes useless.

The object of the invention is to devise an ink cartridge of the type mentioned at the outset, in which the ink reservoir case is ventilated and only the amount of ink required for writing flows out of the cartridge.

The purpose of this is to make the aeration device a hollow body filled with liquid in the type of ink cartridge mentioned at the beginning, and each hollow body is sealed with a diaphragm that is permeable to air but not permeable to liquid. The solution is to provide two vents, one of which seals the reservoir case opening in a fluid-tight manner.

The water in the vented hollow body prevents air from constantly reaching the end of the sump case through the diaphragm unhindered. Only when a certain amount of ink flows out of the sump case and a certain vacuum is formed in the case, a certain amount of air is conducted through the liquid in the hollow body into the sump case.

Although fountain pens constitute a preferred area of application of the invention, the present invention is in no way limited to ink cartridges for fountain pens. It can also be used for fountain pens as well. Furthermore, the present invention can also be applied to ink containers for ink jet printing machines and the like.

Ink cartridges are generally cylindrical or conical. The ink reservoir case is made of plastic.

An ink outlet is provided at one end of the case.

According to the invention, therefore, at the other end of the ink reservoir case, a venting device is attached, which is also designed as a conical or cylindrical hollow body made of plastic. The hollow body forms, as it were, a rear extension of the cartridge. By making the ink reservoir case slightly shorter, the ink cartridge for a fountain pen according to the present invention can be manufactured with the dimensions of a conventional ink cartridge.

The venting hollow body may essentially be adhesively attached to the end of the ink reservoir case opposite the ink outlet, but preferably the venting hollow body is fitted into the chain end of the ink reservoir case. The ventilation hollow body is preferably fixed by welding, although mere clamping, fixing or gluing is likewise possible.

According to experience, an ink cartridge for a fountain pen has a certain lifespan from when it is manufactured until it becomes empty and is discarded. Since a constant evaporation of the liquid, for example water in the vented hollow body, must be allowed for, according to the invention the amount of this liquid is adapted to the expected average life of the ink cartridge. Therefore, the present invention contemplates that the length of the ventilation hollow body is approximately 1/3 to 1/2 of the length of the ink reservoir case.

In particular, the volume of liquid in the vented hollow body is approximately 1/3 to 1/2 of the volume of ink in the ink reservoir case.

Polytetrafluoroethylene (PTFE) has been found to be particularly suitable as a material for the vented hollow body membrane.

To obtain a stable ink cartridge, it is preferred to place the diaphragm on a perforated carrier plate made of plastic.

The present invention further proposes a method for manufacturing an ink cartridge of the above type. This method consists of the following steps: sealing one end of the hollow body with a diaphragm, filling the hollow body with liquid, sealing the other end of the hollow body, and placing the hollow body in an ink reservoir case. A process of inserting the body and a process of melt-sealing the hollow body and the ink reservoir case.

Embodiments of the present invention will be described in detail below based on the drawings.

What each figure shows is as follows: Figure 3: Longitudinal section of an ink cartridge with a ventilation hollow filled with water.

FIG. 4: An enlarged detail of the joint between the ink reservoir case and the venting hollow body of the ink cartridge shown in FIG. 1, in this case one of the septa is partially shown highly enlarged.

FIG. 3 shows a longitudinal section of an ink cartridge consisting of the actual cartridge P and an auxiliary body Z which is used as a ventilation device and is formed as a ventilation hollow body filled with liquid.

The cartridge P has a conical ink reservoir case 11 made of plastic, and an outlet valve 13 is provided on the front end wall 12 of the case. In this case, the counter valve may be a globe valve, for example, and the ink reservoir 11 is filled with ink 14. When the ink outlet 13 is directed downward, an air-filled space 15 is formed above the level of the ink 14.

The cartridge P described so far corresponds to a generally known ink cartridge.

A ventilation hollow body Z is inserted into the other end of the ink reservoir case 11 opposite to the ink outlet 13. The auxiliary body Z is melt-sealed with the ink reservoir case 11.

The auxiliary body used as an aeration device is also made of plastic.The cylindrical hollow body 16 is sealed at both ends with membranes 17 and 18 that are air permeable but impermeable to liquid.The interior of the aeration hollow body is It is mainly filled with water. When the ink cartridge is placed vertically, an air-filled chamber 21 is formed above the water surface.

Diaphragms 17 and 18 are PFTE membranes made of biaxially stretched PFTE, the same as previously described.

Since the total length H2 of the hollow body 16 is set at a ratio of 1:2 to the total length Hp of the original cartridge P,
The volume of water 19 is approximately 1/3 to 1/2 of the volume of ink 14.

As FIG. 4 shows, the diaphragm 18 is placed on the front end of the hollow body 16 and is, for example, welded.

There is a heat seal seam 20 between the outer periphery of the diaphragm 18 and the inside end of the ink reservoir case 11, which interconnects the two parts that make up the ink cartridge.

At the bottom of FIG. 4, the diaphragm 18 is shown enlarged to be very thick. Carrier 18 formed from a perforated plastic plate
The parts 18a and 18b are joined to form a laminate, which is manufactured as a foil from which small plates are punched. Can be done.

The cartridge described above is manufactured as follows. First, one end of the plastic hollow body 16 is sealed with a diaphragm 18 (or 17). The container J thus created is filled with water 19. Next, after sealing the other end of the hollow body 16 with the other diaphragm 17 (or 18), the vented hollow body is inserted into the rear end of the cartridge P filled with ink.
The two are welded together using a method known per se.

When the ink 4 gradually flows out of the ink reservoir case 11 through the ink outlet 13 during use of the fountain pen, the pressure in the space 15 filled with air decreases.

However, since one side of the diaphragm 18 is sealed with water 19, air does not immediately flow in through the diaphragm 18. Only when the pressure in the space 15 drops below a certain value does the air pass through the diaphragm 17, the air chamber 21, the water 19 (in the form of bubbles) and finally reach the space 15 through the diaphragm 18, thus The pressure in the same space increases again, allowing the ink 14 to continuously flow out of the cartridge through the ink outlet 13.

The entire cartridge having the above-mentioned dimensions and having the above-mentioned volume ratio ensures that the nib of the fountain pen is constantly and accurately supplied with as much ink as is required for writing.

By avoiding excessive ink supply, the fountain pen is not smeared with ink.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view of an ink cartridge of the present invention, FIG. 2 is an enlarged sectional view of the part marked ■ in FIG. 1, and FIG. 3 is a longitudinal sectional view of an ink cartridge of another invention. FIG. 4 is a partially enlarged sectional view of FIG. 3. DESCRIPTION OF SYMBOLS 1... Surrounding wall, 2... Outlet, 3... Laminated body, 4... Perforated tube, 51, PTFE-
Diaphragm, 11... Ink reservoir case, 16... Venting hollow body, 17, 18... Diaphragm,
19...Liquid, Z...Aeration device.

Claims (1)

Claims: 1. At one end, the case wall (1) is characterized in that it has an additional vent hole, which is closed with a breathable but ink-impermeable sealing material (3). An ink cartridge such as a fountain pen that has an elongated case with an outlet. 2. An ink cartridge according to claim 1, wherein an additional vent hole is provided at the end of the ink cartridge remote from the outlet (2). 3. The ink cartridge according to claim 1 or 2, wherein the sealing material is formed of a biaxially stretched PTFE membrane (5). 4. The ink cartridge according to claim 3, wherein the fiber length of the diaphragm (5) corresponds to a pore diameter of 0.02 to 5 μm, preferably 0.02 to 2.0 μm. 5. According to claim 3 or 4, the PTFE diaphragm (5) together with the carrier layer (4) forms a laminate (3) covering the additional ventilation holes. Inkipatrone. 6. Ink cartridge according to claim 5, wherein the carrier layer (4) is oriented with additional ventilation holes and is formed from a perforated film of thermoplastic synthetic resin, preferably polypropylene. 7. Ink cartridge according to claim 5 or 6, in which the PTFE diaphragm (5) is covered on both sides by a carrier layer (4). 8. An ink cartridge comprising an ink reservoir case (11) containing ink, the case being equipped with an ink outlet (13) and a venting device (Z), the venting device (Z)
is a hollow body filled with a liquid (19), and each hollow body is provided with a diaphragm (17, 18) that has air permeability but does not allow liquid to pass through.
), one of them (1
8) is an ink cartridge characterized in that the opening of the ink reservoir case is sealed to prevent liquid from passing through. 9. The ink reservoir case (11) is a cylindrical or conical tube made of plastic, and an ink outlet (13) is formed at one end of the tube, and a conical or cylindrical tube also made of plastic is formed at the other end. 9. Ink cartridge for a fountain pen according to claim 8, characterized in that a venting device (Z) formed as a hollow body (16) is fixed. 10. Connect the ventilation hollow body (16) to the ink reservoir case (11)
The ink cartridge according to claim 9, which is inserted into the open end of the ink cartridge. 11. Connect the ventilation hollow body (16) to the ink reservoir case (11)
The ink cartridge according to claim 9 or 10, wherein the ink cartridge is adhered to. 12. Connect the ventilation hollow body (16) to the ink reservoir case (11)
Claim 9, characterized in that the
The ink cartridge according to item 1 or item 10. 13. The ink cartridge according to any one of claims 8 to 12, wherein the liquid is water (19). 14. Claim 9, characterized in that the length (H_2) of the ventilation hollow body (16) is about 1/3 to 1/2 of the length (Hp) of the ink reservoir case (11). Section ~ 13th
The ink cartridge described in any of the paragraphs. 15. The volume of the liquid (19) in the hollow body (16) is approximately 1/3 to 1/2 of the volume of ink in the ink reservoir case (11).
Claims 8 to 1 are characterized in that:
The ink cartridge according to any one of Item 4. 16. The ink cartridge according to any one of claims 8 to 15, wherein the diaphragms (17, 18) are made of biaxially stretched PFTE (polytetrafluoroethylene). 17, the fiber length of the diaphragm (17, 18; 18a) is 0.02
Claim 16, characterized in that it corresponds to a pore size of ~0.05 μm, preferably 0.02-0.2 μm.
Ink cartridge described in section. 18, PTFE membranes (17, 18) are respectively connected to the carrier layer (
18b) to form a laminate, the ink cartridge according to claim 16 or 17. 19. The following process steps: sealing one end of the vented hollow body with a diaphragm, filling the hollow body with liquid, sealing the other end of the vented hollow body, and sealing the vented hollow body with a diaphragm. The ink cartridge according to any one of claims 9 to 18, comprising the steps of inserting the cartridge into the ink reservoir case and melt-sealing the aeration hollow body and the ink reservoir case. Production method.